Ruthenium complexes of phosphine-amide based ligands as efficient catalysts for transfer hydrogenation reactions

This work presents three mononuclear Ru(ii) complexes of tridentate phosphine-carboxamide based ligands providing a NNP coordination environment. The octahedral Ru(ii) ion shows additional coordination with co-ligands; CO, Cl and CH3OH. All three Ru(ii) complexes were thoroughly characterized including their crystal structures. These Ru(ii) complexes were utilized as catalysts for the transfer hydrogenation of assorted carbonyl compounds, including some challenging biologically relevant substrates, using isopropanol as the hydrogen source. The binding studies illustrated the coordination of the isopropoxide ion by replacing a Ru-ligated chloride ion followed by the generation of the Ru-H intermediate that was isolated and characterized and was found to be involved in the catalysis.

Automated summary

This study synthesized three mononuclear Ru(ii) complexes as catalysts for transfer hydrogenation reactions, with tridentate phosphine-carboxamide based ligands providing a NNP coordination environment. These Ru(ii) complexes showed additional coordination with CO, Cl, and CH3OH. The research also revealed the involvement of Ru-H intermediates in the catalysis process.